(Reuters) - Immigration rights groups in a
lawsuit filed on Wednesday accused Arizona Sheriff Joe Arpaio of
overstepping his bounds as a local official by using anti-identity theft
laws to target undocumented immigrants in workplace raids.

Puente Arizona, an immigrant rights groups, filed the lawsuit in
federal court, along with two women who were arrested by Arpaio's
deputies last year and a local minister who contends the sheriff is
squandering his tax dollars by conducting the operations.

The lawsuit represents the latest challenge by advocates for
immigrants against Arpaio, the sheriff of Maricopa County who bills
himself as "America's Toughest Sheriff" and has become a divisive
figure in the national immigration debate.

Arpaio is the only local law enforcement official in Arizona
enforcing state laws that make it illegal for a person to use
information belonging to someone else, such as a Social Security
number, to obtain employment, said Dan Pochoda, legal director of
the American Civil Liberties Union of Arizona, which is one of the
groups representing the plaintiffs.

"We know from past experience that when the (Maricopa County
Sheriff's Office) gets into the business of immigration enforcement,
it's a recipe for discrimination and abuse," Pochoda said in a
statement.

A federal judge last year ordered Arpaio to stop using race as a
factor when making law enforcement decisions, in response to a 2007
lawsuit that tested whether police could target unauthorized
immigrants without also profiling U.S. citizens and legal residents
of Hispanic origin.

In their lawsuit filed on Wednesday, immigrant rights advocates said
Arpaio has no right under the U.S. Constitution to target illegal
immigrants because that is the jurisdiction of the federal
government.

Attorneys who filed the suit are seeking a judge's order requiring
Arpaio from enforcing the identify theft laws. It was filed as a
proposed class action, with attorneys seeking to represent all
workers subject to arrest and detention by Arpaio's office under
those laws.

Arpaio, in a phone interview, said the lawsuit is frivolous, and
that his office has arrested over 800 people in connection with
identity theft by employees.

"Identity thieves will not get sanctuary in Maricopa County as long
as I am sheriff,” Arpaio said. "This is a very serious crime,
identity theft.”

Arpaio said his office does not specifically intend to target
illegal immigrants with the operations but that many of those
arrested turn out to be undocumented.